Which Modified Sgarbossa Rule does this meet? And what is the Rhythm?

A reader sent this ECG and asked " Steve, can this be hyperK? "  He sent no clinical information.What do you think?My answer: " This is inferior OMI. "  There is LBBB and an with a false negative Modified Sgarbossa. "The rhythm is also interesting, but does not affect the diagnosis of OMI:there are also no P-waves before the QRS complex.  The wide complex suggests an idioventricular rhythm, in fact it is an accelerated junctional rhythm followed by Left Bundle Branch Block (LBBB).  Idioventricular rhythm would have a slower QRS onset, similar to VT (and it can ' t be VT also because it is too slow). So this is an accelerated junctional rhythm with retrograde P-waves and LBBB).(I confirmed this with the rhythm master, Ken Grauer, who annotated the 2nd EKG below to show the retrograde P-waves).There are obvious hyperacute T-waves in inferior leads and also in V5 and V6,but it does not clearly meet any of the 3 Smith Modified Sgarbossa criteria.  There is some minimal concordant ST elevation in lead III (some might measure 1 mm, but it is not consistent in the only 2 complexes), and just less than 1 mm of concordant ST depression in V1-V3.  There is also no ST elevation that is greater than 25% of the preceding S-wave (no proportionally excessively discordant ST Elevation).  But there isone other rule that we derived and validated as VERY SPECIFIC, though probably not sensitive, for OMI:Discordant ST depression (or STE) that is out of...
Source: Dr. Smith's ECG Blog - Category: Cardiology Authors: Source Type: blogs